Discussion Forum - Northstar Chevelle Club

69SSConv · Active Member

Good price for Vortec 350 Heads?

SShink · 3K+ Club

The 350 in the vert runs great, but... the exhaust valve guides must be worn because it puffs some blue oil smoke on restarting after it's been run and sits for a little while.

So, if I wouldn't mind putting $500 or so into it to liven it up a little bit. Found these vortec heads for $250. Worth it? Will they work with a '74 vintage stock 350?

It's all Chris P.'s fault because he mentioned doing something like this to me when we were talking...

http://minneapolis.craigslist.org/wsh/pts/3287767945.html

set of chevy 906 vortec 350 heads

ARP rocker arm studs
New comp springs 310 lbs open pressure
3 angle valve job
new valves 1.94/1.5
new posative valve stem seals
Resurfaced

67ss · 1K+ Club

That is a good price for the work that looks to have been done to them. I would find out if the valve guides were cut down for running higher lift cams. You also need the vortec specific intake and rocker arms. I think I have a set of stock rockers arms laying around you can have.

They will bolt right on to your motor. The only thing I found that usually needs to be done is a coolant bypass hose from the bottom of the thermostat going into one of the heater hoses. There is usually a pipe fitting on the intake right under the thermostat. These should bump your compression up and if you stepped up the cam it would make a nice little motor.

SShink · 3K+ Club

Thanks Chris.

Do you have a cam recommendation for general street use? I'm assuming keeping it under .500 int/ex lift?

Is the coolant bypass recommended because of coolant flow issues in the heads?

Sounds like stock pushrods would also work?

Got that engine running stand available yet?

67ss · 1K+ Club

I would go with the 330 crate motor cam from GM I think would be a good choice. If those valve guides have been cut down you could add 1.6 rockers to up the lift some. Guess it depends on how much money you really want to spend. You might also chat with loren the motor he built for his kids camaro would be similar to what you want to do. See what cam he used with his vortec heads I think his made 310-320 horse.

Yes the engine stand is ready for use, we can break it in.

bowtie · Secretary

careful with 1.6 full roller rockers and factory valve covers. Mine were hitting just at the outer corners. A slight clearancing would be necessary or finding a taller cover.

I second the spring issue Chris P brought up. Some springs don't need it based on diameter. Mine did.

67ss · 1K+ Club

I put the Lunati 60102 in the motor for that 55 but I also stepped up the lift with 1.55 rocker arms. Hopefully will get it fired on the stand here shortly to see how it sounds.

SteveS · Super Poster

I had a Lunati 60103 with Sportsman 2 heads on a 350 before the LS swap. Never had it on a dyno, but I was pretty impressed with it.

69SSConv · Active Member

I just looked, I have 1.5 roller rockers.

67ss · 1K+ Club

SShink wrote:
Is the coolant bypass recommended because of coolant flow issues in the heads?

There is a bypass hole that is not in the vortec heads. So it needs the bypass hose to get the thermostat to open. I fought this issue with my car when I first got it together.

SShink · 3K+ Club

Thanks for all the feedback everyone.

After thinking about this further, by the time I paid for a new intake, center hole valve covers, probably a new cam/lifters since I wouldn't be able to hold myself back with it blown apart, I'd be in the $500-1K range. So, I might as well hold out for an LS engine to come my way.

bowtie · Secretary

It's been done, almost to death but it IS the smarter way to go now. I already have a cool idea for a unique LS twist--do you have an operational cowl hood? You can mount a cathederal port LS intake backwards. You could make an air plenum to direct that cowl air into the manifold. The only issue might be the oil pressure fitting, but that can be moved down to the oil pan side cover.